What EPA's radon map says about Logan County

EPA's own radon map rates Logan County zone 1 - highest potential, predicting a county-wide average indoor level above 4 pCi/L. Nationally that's the 89th percentile for radon potential — Logan County outranks 89% of every county EPA has rated.

How Logan County compares

About 46,085 people live in Logan County, Ohio, spread over 458.508 square miles. Population density there runs about 101 people per square mile. Among counties sharing Logan County's EPA zone, it outranks 68% of them by population. EPA's geology-based Region 5 groups Logan County with 523 other counties nationally sharing its underlying rock and soil profile.

What this actually means for a house in Logan County

Where the national indoor average runs about 1.3 pCi/L, Logan County's Zone 1 rating puts its predicted county average above EPA's 4 pCi/L action level itself. Being in Zone 1 raises the odds Logan County homes test above the action level, but it does not mean any specific house does — EPA recommends every home be tested, in every zone, because the only way to know is to test.

Next steps for a home in Logan County

Mitigation cost doesn't depend on Logan County's zone — it depends on the house's foundation. A typical system runs $800–$2,500 (about $1,200 typical), and testing first is what tells you whether that's needed at all.

Find Ohio's state radon program

Logan County's test kit answers today; a Airthings radon monitor keeps answering for Logan County over time. Affiliate link, RadonZoneCheck earns a commission there, at no extra cost to you. Code RADONZONE-10OFF takes 10% off at checkout.

More on how this number was built

The methodology guide shows exactly which EPA and Census sources feed Logan County's numbers. Whatever zone Logan County carries, the zone explainer covers what it does and doesn't tell you about any one house.